1 2 /* 3 * Copyright 2011 Google Inc. 4 * 5 * Use of this source code is governed by a BSD-style license that can be 6 * found in the LICENSE file. 7 */ 8 #include "SkBoundaryPatch.h" 9 10 SkBoundaryPatch::SkBoundaryPatch() : fBoundary(NULL) {} 11 12 SkBoundaryPatch::~SkBoundaryPatch() { 13 SkSafeUnref(fBoundary); 14 } 15 16 SkBoundary* SkBoundaryPatch::setBoundary(SkBoundary* b) { 17 SkRefCnt_SafeAssign(fBoundary, b); 18 return b; 19 } 20 21 static SkPoint SkMakePoint(SkScalar x, SkScalar y) { 22 SkPoint pt; 23 pt.set(x, y); 24 return pt; 25 } 26 27 static SkPoint SkPointInterp(const SkPoint& a, const SkPoint& b, SkScalar t) { 28 return SkMakePoint(SkScalarInterp(a.fX, b.fX, t), 29 SkScalarInterp(a.fY, b.fY, t)); 30 } 31 32 SkPoint SkBoundaryPatch::eval(SkScalar unitU, SkScalar unitV) { 33 SkBoundary* b = fBoundary; 34 SkPoint u = SkPointInterp(b->eval(SkBoundary::kLeft, SK_Scalar1 - unitV), 35 b->eval(SkBoundary::kRight, unitV), 36 unitU); 37 SkPoint v = SkPointInterp(b->eval(SkBoundary::kTop, unitU), 38 b->eval(SkBoundary::kBottom, SK_Scalar1 - unitU), 39 unitV); 40 return SkMakePoint(SkScalarAve(u.fX, v.fX), 41 SkScalarAve(u.fY, v.fY)); 42 } 43 44 bool SkBoundaryPatch::evalPatch(SkPoint verts[], int rows, int cols) { 45 if (rows < 2 || cols < 2) { 46 return false; 47 } 48 49 const SkScalar invR = SkScalarInvert(SkIntToScalar(rows - 1)); 50 const SkScalar invC = SkScalarInvert(SkIntToScalar(cols - 1)); 51 52 for (int y = 0; y < cols; y++) { 53 SkScalar yy = y * invC; 54 for (int x = 0; x < rows; x++) { 55 *verts++ = this->eval(x * invR, yy); 56 } 57 } 58 return true; 59 } 60 61 //////////////////////////////////////////////////////////////////////// 62 63 #include "SkGeometry.h" 64 65 SkPoint SkLineBoundary::eval(Edge e, SkScalar t) { 66 SkASSERT((unsigned)e < 4); 67 return SkPointInterp(fPts[e], fPts[(e + 1) & 3], t); 68 } 69 70 SkPoint SkCubicBoundary::eval(Edge e, SkScalar t) { 71 SkASSERT((unsigned)e < 4); 72 73 // ensure our 4th cubic wraps to the start of the first 74 fPts[12] = fPts[0]; 75 76 SkPoint loc; 77 SkEvalCubicAt(&fPts[e * 3], t, &loc, NULL, NULL); 78 return loc; 79 } 80 81
